In manufacturing processes for a semiconductor device, patterns are transferred onto the surface of a bare wafer and then unnecessary sections of the wafer are removed by etching to form electrical circuits. In the semiconductor device manufacturing processes used to form the circuits, foreign substances sticking to the surface of the wafer, defects present on the wafer surface, and the like are major causative factors in the deterioration of a production yield.
Foreign substances sticking to the wafer surface, and defects present on the wafer surface are managed in each manufacturing process, and a surface inspection apparatus detects these foreign substances and defects at high sensitivity and high throughput. In the surface inspection apparatus, the surface state (e.g., surface roughness) of the object under measurement is another crucial factor governing the photolithographic performance of the manufacturing apparatus. During the surface inspection, the surface state of the wafer is also an important factor relating to detection sensitivity, and thus has a substantial need for measurement.
Examples of conventional apparatuses and techniques for inspecting defects and/or measuring surface states are seen in Patent Documents 1 to 7 listed below.